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Robin Verhagen-Guest edited this page Aug 30, 2020 · 64 revisions

NXtel Questions

What is NXtel?

NXtel is a complete viewdata BBS system using teletext graphics, designed to be used by modern, retro and mobile devices. We provide a dedicated client for the ZX Spectrum Next, a server, and a page manager for creating and editing content.

NXtel is accessed over tcp/ip using a network card, or a wifi modem retro devices.

NXtel Welcome Page

How do I use NXtel with a ZX Spectrum Next?

Follow the installation instructions for the most recent release on the NXtel Releases page.

How do I use NXtel without a Spectrum Next?

Right now, there are three really easy ways to run NXtel.

The very easiest way is to use Simon Laszcz's vd-view client in your web browser.

Mike Dailly's CSpect emulator for the Spectrum Next runs NXtel on Windows, Mac OS and linux. Because it's a Next emulator, you can see NXtel in its full glory, as people with a real Next would! Follow the instructions here.

Richard T Russell's BBC BASIC for SDL2.0 Telstar client runs on Windows, Mac OS, linux, android and ioS. Follow the instructions here.

How do I get my ZX Spectrum Next online?

You need an ESP 8266-01 wifi module. If you backed the Spectrum Next Plus, Accelerated, Yours Truly or Ultimate tiers of the Kickstarter campaign, your Next will be fitted with an ESP module.

Otherwise, you should purchase an ESP 8266-01 module immediately. But don't worry, they're very cheap. If you don't mind waiting for them to arrive from China, they can be bought from eBay for less than £1.50, with free shipping. They can also be obtained next-day from Amazon Prime, if you can't wait that long. More information on fitting and configuring the module can be found at the Official Spectrum Next Wiki ESP8266-01 page.

If you have a hobbyist mentality, I also recommend you buy an ESP-01 USB adaptor. Although sold as programmer adaptors, these also allow you to use or talk to an ESP-01 directly from your PC, which can be very useful for troubleshooting. There's some anecdotal evidence suggesting that the red OpenSmart adaptors with switches might be easier to get working.

Can I run NXtel in an emulator?

The CSpect Next emulator now emulates the ESP-01 wifi module, and will also talk to a physical ESP plugged into a USB socket. Read this tutorial explaining how to run NXtel inside CSpect.

Recent versions of the Zeus development emulator will also talk to a physical ESP plugged into a USB socket. A monochrome version of NXtel will run inside Zeus, and in fact this is how NXtel is primarily developed. Read this tutorial explaining how to run NXtel inside Zeus.

Why does the hash key not do anything?

NXtel follows the conventions Prestel established in the 1970s. Prestel was originally operated from a telephone keypad over a modem, so it only used keys 0 to 9, * (Star) and # (Hash). * was the special function key and # was the send key. Later, Prestel was used from terminals and home computers, and send was typically mapped to the ENTER or RETURN keys. However the onscreen pages continued to refer to send as #.

Likewise in the present day, pages on the NXtel and TELSTAR servers refer to send as #, and the NXtel client (and other modern clients like TELSTAR and vd-view) map it to the ENTER key.

How do I go directly to a page number?

On the ZX Spectrum Next keyboard, to go to page 91 (for example):

  1. Press SYMBOL SHIFT
  2. Type B (this sends * to the server)
  3. Release SYMBOL SHIFT
  4. Type 9 (this sends 9 to the server)
  5. Type 1 (this sends 1 to the server)
  6. Type ENTER (this sends ENTER to the server)

Why are the keys I type are not echoed to the screen as I type them?

This is the way Prestel and similar services have always worked, since the 1970s. Modern servers such as TELSTAR and Tetrachloromethane don't normally either, even when connected to from other viewdata clients. Strictly speaking remote echo is something that the server does, although the client also has to support it.

In the future, the NXtel server and client may support remote echo on certain pages, such as when login details are entered or interactive adventure games are played.

Currently a short beep is made every time a key is sent to the server. No beep is made when SYMBOL SHIFT, CAPS SHIFT or EXTEND MODE are held or released.

Why do I get a core version error message loading NXtel?

NXtel requires the Next core to be version 2.00.26 or higher. The loader will tell you if your core is too old. To update the core, follow the update instructions at the Latest Distro page.

Why does my NXtel crash during loading, or refuse to load?

NXtel requires a recent copy of the .nexload dot command to run. If NXtel doesn't run on your machine, copy this file to the c:/DOT directory, then try to run NXtel again.

Why does NXtel sometimes freeze up?

If you have a Real Time Clock (RTC) fitted to your Next, NXtel also requires a recent copy of RTC.SYS. Copy this file to the c:/NextZXOS directory, then try to run NXtel again.

Of course it could also be a bug! NXtel is still in development, so please create a new GitHub issue or find me in the ZX Spectrum Next Facebook group.

What's the difference between NXtel's WENDY and TEST servers?

WENDY is the main live server, where all the interesting content is. This is what you should normally connect to.

TEST is where we try out and test new features, without breaking the main live server. Sometimes you might need an experimental test version of the NXtel client to connect to this, which you can find here.

How do I connect to other servers?

There are a few other viewdata servers, maintained by enthusiastic retro communities. Tetrachloromethane is an anarchically humorous server which been on the scene the longest. TELSTAR has a BBC Micro/Acorn focus, and Teefax is an established broadcast-oriented teletext service which now also has an experimental viewdata presence.

Not all of the other servers fully work with the Next client yet, but we are actively working on ironing out the niggles.

You can add servers to the Next client by editing the NXtel.cfg file.

How do I edit the list of servers in NXtel?

The NXtel.cfg file always exists on the Next SD card, in the same directory that NXtel.nex resides. If it is missing, a new one will be created next time you run NXtel.

Mount the SD card on your PC, and open this file in your favourite text editor. NXtel doesn't mind what line-endings are used in the file, so feel free to do this on Windows, Mac OS, Linux, or even the Next itself (if you have a native text editor!).

Copy an existing line, and change the URL number, description, hostname and port to the server's details. A maximum of 8 server entries are currently supported, and the URL numbers must run consecutively starting with 1. For example:

URL7=My New Server,"TCP","my.hostname.co.uk",1234

What is telesoftware?

Telesoftware is a means of transmitting software (games, utilities and other programs) via TV channels, dial-up connections or over the internet, usually using teletext-based computer systems.

It was pioneered in the UK during the 1970s and 1980s, and became popular (although still somewhat niche) due to the success of the BBC Computer Literacy Project, and the incorporation of a teletext chip in the Project's flagship BBC Micro home computer.

How do I download telesoftware?

Connect to the WENDY server and navigate to page *8000#. Use the menu on that index page to select the desired section (Next, Spectrum, etc). Select the menu number for the software item you want to download. The first frame displayed (the one ending with a) is a descriptive summary of the software. Press the ENTER key. The next page is the telesoftware header. It will say Press DOWNLOAD key to start at the bottom of the screen. It also contains the filename at the top of the screen. You will need this info later.

If you are using the Next client, press the SymbolShift+D keys (Ctrl+D keys on a ps/2 keyboard). This is a simultaneous press like you might do on a PC, not one after the other like a 48K Spectrum.

If you are using the BBC BASIC SDL2.0 client, press the F5 function key.

Wait while the software is downloaded. A progress bar and percentage will be displayed at the bottom of the screen, each time a new frame is downloaded. Download will stop when the last frame is downloaded (usually a partial frame).

If you are using the Next client, reboot the Next with the F4 function key (or MF+4 keys on a Next or rubber keyboard), and locate the file in the NextZXOS browser to launch it.

If you are using the BBC BASIC SDL2.0 client and the file can be automatically launched (BBC BASIC programs only), you will be asked whether you want to run the program. Press the Y key.

Soon, the Next client will support launching the downloaded file directly from NXtel!

Can I log into NXtel securely?

Not yet. We have plans to support anonymous connections in the Next client soon. The server will recognise you between sessions, and offer you personalised content. You will be able to claim an anonymous user in the web dashboard, and convert it to a full user.

Later, we also have plans to support semi-secure logins using usernames and hashed passwords.

Remember that videotex is a simple plain text tcp/ip protocol, and using SSL/TLS to encrypt the entire connection is not currently feasible, so you should never consider the connection to be secure against a man-in-the-middle attack.

However, the Next Z80N CPU is fast enough (at nearly 14MHz) to hash passwords using state-of-the-art SHA-3 hashing algorithms, so we hope to offer a reasonable level of protection against identity spoofing.

Once anonymous or hashed connections are available, we plan to add mailboxes and user messaging features.

Is there a version of NXtel for the 48K or 128K ZX Spectrum?

Not yet. The current Next client uses many Next-specific features, and we wanted to make something new and exciting for the launch of the Next.

However, we are planning another version of NXtel that will work with a WiFi modem plugged into the RS-232 port of the ZX Spectrum 128K, +2, +2A and +3 models.

Then after that, perhaps a version that will work with the Spectranet interface...

Why no attribute clash?

The NXtel client for the Spectrum Next uses layer 2, which can display 256 colours on screen at once. Each pixel on the 256x192 resolution can individually be a different colour, chosen from a palette of 512 colours. This screen mode is specific to the Spectrum Next.

How fast can NXtel run and download data?

The NXtel client for the Spectrum Next currentlty runs at 115,200 bits per second, which is the default baud rate of the ESP8266-01 wifi module in the Next.

Can I use NXtel with esxDOS instead of NextZXOS?

No, unfortunately. NXtel.nex is loaded using the .nexload dot command, and esxDOS dot commands prefer to exit to BASIC instead of a machine code program.

What's the difference between NXtel, ViewData, videotex, teletext and a BBS?

Why is it called NXtel?

The NXtel name is a nod to its 1970s ancestor, Prestel. Prestel was short for PRESs TELephone, as it originally used a telephone pushbutton keyboard to communicate with remote servers. Although NXtel uses tcp/ip rather than telephones and modems, we still thought NXtel was a good name. The NX stands for NeXt.

What is the NXtel Client?

What is the NXtel Server?

What is the NXtel Page Manager?

How do I get started creating NXtel or teletext pages?

The NXtel Page Manager uses a special version of the Edit-TF teletext editor.

You can play around with Edit-TF in your web browser, and learn to create pages without needing a NXtel account. Pages you create are stored in the long Edit-TF URL, so remember to bookmark your creations for later use!

Here is an Edit-TF video tutorial, and a short how-to document.

Can I or my retro group run our own NXtel server?

Why server operating system is NXtel hosted on?

Why language is the NXtel client written in?

Does NXtel support other languages?

How can I get involved with creating content pages on NXtel?

How can I get involved with developing NXtel?

Is NXtel open source?

ESP-8266-01 Questions

What is the ESP 8266-01 wifi module?

An ESP8266 ESP-01 module provides access to 802.11 b/g/n 2.5 Ghz wifi networks. It provides a modem-like "AT" interface to the host computer.

How is the ESP supported on the ZX Spectrum Next?

The wifi module makes use of the on-board UART (Universal Asynchronous Receiver-Transmitter) of the Spectrum Next. The ESP8266-01 page on the official Spectrum Next wiki has more information.

How can I use the ESP in my own projects?

Yes, the Spectrum Next Developers Wiki describes how to make a connection using the module from Spectrum BASIC.

How can I monitor or debug ESP wifi traffic?

Can I update the firmware on my ESP?

I see that NXtel does <Some Thing> but I had a great idea that you should make it do <Some Completely Different Thing> instead

No, do it yourself. NXtel is open source.

General Questions

I know about the ZX Spectrum, but what is the Spectrum Next?

What is TELSTAR?

What is Tetrachloromethane?

Can I use the NXtel teletext renderer or INI file parser in my own projects?